Color couplers for photographic color images



United States Patent Germany No Drawing. Filed June 5, 1962, Ser. No. 200,070

Claims priority, application Germany, July 28, 1961,

15 claims. (or. 96-55) This invention relates to novel organic compounds' which are very useful as color coupler for color photography as Well. as to a color-photographic material containing said coupler components and a process for the production of cyan dyestufi? photographic images by reactin the color couplers according to the invention with the oxidation products of color-forming developers.

In the production of photographic color images, it is common practice to use derivatives of phenol and naphthol as color couplers for the cyan image. Indophenol dyestuffs are formed upon coupling with the oxidation products of a primary aromatic amine developer. Thus, for example, in U.S. Patent 2,472,910, 5,6,7,8-tetrahydrol-hydroxy-2- and -3-naphthamidobenzaldehydes and their lower a-cetals are described as cyan couplers in photographic material.

The dyestulfs obtained by coupling with the known color developers, such as N-dieth-yl-p-phenylene diamine, have desirable spectral properties, but they have only a low resistance to heat. Furthermore, it is known to use the l-hydroxy-Z-naphthoic acid anilide of l-amino-2- methyl-octadecylaminobenzene-S-sulphonic acid as a color coupler. Cyan dyestuffs obtained with this color coupler turn yellow as does the coupler, on exposure to light.

An object of the present invention is to provide novel color couplers. A further object is to provide photographic elements which contain a new class of tetrahydronaphthol derivatives which are stable to heat and light and which form upon development with a color-forming developer a cyan dye of the proper spectral characteristics for rnu-lti-col'or-photography. Still other objects will be apparent to those familiar with color-photography from the following description.

It has been found that cyan dyestufis which are resistant to both light and heat and which have a very fine grain and favourable absorption properties are obtained by using, as couplers, compounds of the following general formula:

wherein the symbols R to R have the following meaning:

R :H, SO3H or their salts with alkali or alkaline earth metals, ammonia or amines, preferably however with alkali metals k al-kyl with 1 to 5 carbon atoms R =alkyl with 8 to 18' carbon atoms R =H, SO H, SO NH it being possible for the amino group to be substituted by short-chain aliphatic radicals or by aryl groups.

Patented Apr. 5, 1966' These new color couplers are prepared" by reacting the phenyl ester of 5,6,7,8-tetrahydro-l-hydroxy-naphthoic acid-(2) with an amine of the following general formula RzI I 3 in which R R and R have the previously specified meanings.

The anilides of tetrahydro-l-hydroxy-naphthoic acid- (2) or -N-ph.enyl-substit,uted 1-hydroxy-5,t6,7,S-tetrahydrO-Z-naphthamides which are formed are purified by treatment with glacial acetic acid or alcohol. The compounds may be sulphonated in the p-position to the hydroxyl group by subsequent action of concentrated sulphuric acid in order to increase the alkali solubility.

Examples of suitable couplers for the production of. the cyan dyestuifs are:

N [2 (N methyl N n octadecylamino): 5. (N- methylsulfamoyl)phenyl] 1 hydroxy 5,6,7,8 tetrahydrO-Z-naphthamide.

Coupler 2:

Hz O H S 0311 I l IEI I Eff W CO.N-

' l Hrk/ H3C.N C1BH31 N [2 (N methyl N n octadecylamino) 5 sulfophenyl] -1-hydroxy-5,6,7,8-tetrahydro-2-naphthamide.

Coupler 3:

s o2.N(o H3) 2 H2 con-Q l H2 HsC .NC1BH31 HaH N [2 (N n pentyl N n octadecylamino) 5- sulfophenyl] 1 hydroxy 5,6,7,8 tetrahydro 2- naphthamide.

Coupler 6:

OH S 11 N [2 (N n propyl N n dodecylamino) 5- sulfophenyl] 1 hydroxy 5,6,7,8 tetrahydro 2- naphthamide.

N [2 (N ethyl N n heptadecylamino) s (N- tolylsulfarnoyDphenyl] 1' hydroxy- 5,6,7,8 tetrahydro-2-naphthamide.

Coupler 8:

H2 SOsH N [2 (N n butyl N n dodecylamino)phenyl]- 1-hydroxy-5,6,7,8-tetrahydro-2-naphthamide.

EXAMPLE 1 Production of coupler 1 29.5 g. of phenyl l-hydroxy-5,6,7,8-tetrahydro-2-naphthoate, prepared by reaction of 1-hydroxy-5,6,7,8-tetrahydro-Z-naphthoic acid with phenol in the presence of POCl were heated with 47 g. of 2- (N-methyl-N-n-octadecylamino) 5 (N methylsulfamoyDaniline (M.P. 83 C.) in a flask at a temperature of 190200 C. The phenol split olf was distilled off. After completion of the reaction, the contents of the flask were cooled to about 100 0., dissolved in 60 ml. of acetone and the resulting solution diluted with 300 ml. of methanol. After standing overnight, the precipitated product was suction-filtered and purified by recrystallization from methanol.

Yield: 56 g., M.P.=74 C.

Sulphonation 50 g. of the product thus prepared were slowly introduced, while stirring, into 300 ml. of concentrated sulphuric acid at 50 C. 56 gfof sulphonated product were obtained after working up in the customary manner.

Photographic application A solution of 1.5 g. of the color coupler in 15 ml. of 1- normal sodium hydroxide solution was added to m1. of a photographic silver bromide emulsion. The emulsion was applied to a prepared film support and dried. After exposure, the film was developed in the following developer:

G. N-diethyl-p-phenylene diamine-H SO 2.8 Sodium carbonate 70.0' Sodium sulphite 2.0 Sodium bromide 2.0

Made up with water to 1000 ml.

After development, the film was rinsed, bleached and fixed. A cyan image was obtained.

The dyestulf thus obtained remained unaltered as regards color tone and density on being treated for 7 hours at 100 C. (Density before treatment: 2.4; density after. treatment: 2.4.)

A comparison dyestulf of l-hydroxy-5,6,7,8-tetrahydro- 2-naphthamidobenzaldehyde (US. Patent 2,472,910) and the oxidation product of N-diethyl-p-phenylene diamine was substantially destroyed when subjected to the aforementioned treatment. (Density before treatment: 2.9; density after treatment: 0.18.)

EXANIPLE 2 Production of coupler 2 29.5 g. of phenyl 1-hydroxy-5,6,7,8-tetrahydro-2-naphthoate and 53.0 g. of the sodium salt of 3-amino-4-(N- methyl-N-n-octadecylamino)-benzenesulfonic acid (90 percent) were slowly heated to C. in 200 ml. of o-dichlorobenzene. About 150 ml. were distilled off within 3 hours and the temperature rose to C. The residue was then diluted with 150 ml. of glacial acetic acid at approximately 100 C. On cooling, the sodium salt of color coupler 2 crystallized out.

Photographic application A solution of 1.5 g. of color coupler 2 in 15 m1. of dilute sodium hydroxide solution was added, as in Example l, to a gelatino-silver bromide emulsion, The resulting emulsion was applied to baryta-coated paper, dried, exposed to light and developed in the developer employed in Example 1. The further processing was carried out as described in Example 1.

The color image thus obtained was subjected to a lightfastness test by exposing it to sunlight for 5 days. After this time, the unreacted color coupler and the dyestutf obtained by coupling were scarcely changed. The comparison color coupler l-hydroxy-2-naphthoic acid-[2'-methyln-octadecylamino-5'-sulphonic acid]-anilide, showed upon this test strong yellowing and the coupling dyestulf had faded appreciably by this time.

EXAMPLE 3 Production of coupler 3 29.5 g. of phenyl 1-hydroxy-S,6,7,8-tetrahydro-2-naphthoate were heated with 48.1 g. of Z-(N-methyl-N-noctadecylamino-S-(N-n-dimethylsulfamoyl)aniline (M.P. 102 C.) to ISO-190 C., as described in Example 1. Working up was efiected as described in Example 1.

Photographic application 1.5 g. of coupler 3 were dissolved in a mixture of 3.0 g. of dibutyl phthalate and 10 ml. of ethyl acetate.v The resulting solution was emulsified in 80 ml. of water con taining 0.2 g. of lauryl sulphate. Part of the water and the ethyl acetate were evaporated off by heating the solution. The remaining dispersion was added to 100 ml. of

a photographic gelatino-silver halide emulsion. The emulsion was applied in the usual manner to a prepared film support. After exposure, the film was developed and processed as described in Example 1.

The compounds according to the invention may be used either in the developing solution or in the sensitive emulsion layers. Where the compounds are of suitable molecular size, they may be incorporated in the sensitive emulsion layer or in one of the layers of a multi-layer material. The incorporation may be achieved either in the form of an aqueous alkaline solution or by dissolving the color coupler in an organic solvent, if desired with the addition of a sparingly soluble organic crystalloid, and by emulsifying said solution into the silver halide emulsion. The processing of the exposed color material, containing in one layer a cyan coupler according to the invention, is accomplished in a manner well known by first developing the material with a developer composition containing a color forming developer. Said developers generally speaking are characterized by a content of a pri mary amino group or a substituted amino group, the substituent of which being split oif during the development, e.g. as described in German specification No. 926,713. Very useful color developers are for example N,N-diethylp phenylene-diamine, N-ethyl-N-hydroxy-ethyl-p-phenylene-diamine, N-butyl-N-sulphobutyl-p-phenylene-diamine, N ethyl-N-methyl sulfoamino-ethyl-p-phenylene-diamine or derivatives thereof being substituted in the phenylene nucleus, furthermore, 4-aminopyrazolone and derivatives thereof. The developer composition may be alkalized by alkali-metal carbonates, tertiary alkali-metal phosphates or alkali-metal hydroxides. The developers may contain any stabilizing agents, anti-fog agents and compounds protecting the composition against oxidation such as alkali sulphites or salts of hydroxylamine. The developing is followed by bleaching and fixing the color films. These procedures are well known to any person having ordinary skill in the art and need not to be described in detail.

Our color couplers may be used for the production of colored photographic images in layers of gelatin or other binding agents for the silver halide, such as organic esters of cellulose, polyvinyl alcohol, synthetic resins or the like.

The support for the emulsion may be a transparent material, such as glass, cellulose esters, polycarbonates o-r polyesters, in particular on the basis of ethylene glycol and terephthalic acid, or a non-transparent reflecting material, such as paper, in particular baryta-coated paper, or an opaque cellulose ester.

The emulsion containing the color coupler according to the invention may be coated as a single layer on the support or as one of a series of superposed layers on one or both sides of .the support. The superposed layers may be differentially sensitized to record natural colorphotographic images in the well-known manner. The light-sensitive layers containing the color couplers according to the invention may be composed of simple or mixed silver halides which may contain the usual sensitizers, desensitizers, stabilizers, fog inhibitors, emulsion hardeners, etc. Suitable types include silver chloride, silver bromide, silver chloro-bromide, silver chloride-bromide-iodide, silver bromide-iodide, etc., which may contain cyanine, carbocyanine, polymethine cyanine, cyazine, carbocyazine, pseudocyanine, kryptocyanine, mercocyanine, rhodanine, etc., salts and bases. The silver halide layers are anchored to the supports by means of the usual subbing solutions. Such solutions are also useful for anchoring dye component layers to bases.

What is claimed is:

1. A process for the production of cyan-colored photographic images which comprises developing a photographic material comprising an exposed silver halide emulsion layer containing a cyan coupler that is capable of developing a cyan-colored image upon reaction with the oxidation product of a primary amine color-forming developer, bleaching and fixing the developed material, said cyan coupler having the following general formula:

in which R is a radical of the group consisting of hydrogen and sulfo; R is an alkyl radical having up to 5 carbon atoms; R is an alkyl radical having from 8 to 18 carbon atoms and R is a radical of the group consisting of hydrogen, sulfo and -SO N(X) in which X is a radical of the group consisting of hydrogen, lower alkyl and aryl.

2. A process as defined in claim 1 in which the cyan coupler has the following formula:

3,. A process as defined in claim 1 in which the cyan coupler has the following formula:

I ll:

4. A process as defined in claim 1 in which the cyan coupler has the following formula:

5. A process as defined in claim 1 in which the cyan coupler has the following formula:

6. A photographic silver halide emulsion layer containing a cyan coupler that reacts with the oxidation product of a primary amine color-forming developer to form a cyan-colored image, the cyan coupler having the following general formula:

In OH 4 II E IIz C-N- I 2 3 H2 R1 in which R is a radical of the group consisting of hydrogen and sulfo; R is an alkyl radical having up to 5 carbon atoms; R is an alkyl radical having from 8 to 18 carbon atoms and R is a radical of the group consisting of hydrogen, sulfo and SO N(X) in which X is a radical of the group consisting of hydrogen, lower alkyl and aryl.

7 8 7. A photographic silver halide emulsion layer as dc in which R is a radical of the group consisting of hydrofined in claim 6 containing a color-coupler having the gen and sulfo; R is an alkyl radical having up to carbon following formula: atoms; R is an alkyl radical having from 8 to 18 carbon H atoms and R is a radical of the group consisting of hydro- H: OH S Oz.N.CHs 5 gen, sulfo and SO N(X) in which X is a radical of the l H group consisting of hydrogen, lower alkyl and aryl. H2 C0-N 12. A photographic element as defined in claim 11, at least one layer of which contains a color coupler having H H3G.NC14H31 the following formula:

H o a o lifa 03H [2 H 5| 2 l ah 8. A photographic silver halide emulsion layer as de- L fined in claim 6 containing a color-coupler having the I following formula: HT IRON-43151130 H l H: H GO.N 13. A photographic element as defined in claim 11, at I least one layer of which contains a color coupler having 11 HaC.N-U1s a1 the following formula:

fig C4110 9. A photographic silver halide emulsion layer as defined in claim 6 containing a color-coupler having the H2 CO.N following formula:

IiIg (|)H SO2.N(CH3)3 HP HJC L\II CXBHST H CO.N' Ha I V 14. A photographic element as defined in claim 11, at H H3C'N Cmm' least one layer of which contains a color coupler having the following formula:

II 10. A photographic silver halide emulsion layer as de- 2 1 s|02-N.CII3 fined in claim 6 containing a color-coupler having the 11 following formula:

1 (IJHB Hr- HaC .N-C |sHs7 H2 011 SO2.N I

I 40 H2 SOaH H CO'N 15. A photographic element as defined in claim 11, at l least one layer of which contains a color coupler having H H3C N CH the following formula:

I H I 11. A photographic element having superposed silver II CO.N- halide emulsion layers sensitive to different regions of the 'visible spectrum, one of said layers containing a cyan H2 H;G.NCmH31' coupler that reacts with the oxidation product of a primary amine color-forming developer to form a cyan- H2 colored image, the cyan coupler having the following general formula: References Cited by the Examiner OH R4 UNITED STATES PATENTS H H 2,324,832 7/1943 Frohlich et al. 96-100 re-N 2,472,910 6/1949 Martin 96 H,- /N\ NORMAN G. TORCHIN, Primary Examiner.

R1 R3 J. T. BROWN, Assistant Examiner. 

1. A PROCESS FOR THE PRODUCTION OF CYAN-COLORED PHOTOGRAPHIC IMAGES WHICH COMPRISES DEVELOPING A PHOTOGRAPHIC MATERIAL COMPRISING AN EXPOSED SILVER HALIDE EMULSION LAYER CONTAINING A CYAN COUPLER THAT IS CAPABLE OF DEVELOPING A CYAN-COLORED IMAGE UPON REACTION WITH THE OXIDATION PRODUCT OF A PRIMARY AMINE COLOR-FORMING DEVELOPER, BLEACHING AND FIXING THE DEVELOPED MATERIAL, SAID CYAN COUPLER HAVING THE FOLLOWING GENERAL FORMULA: 